Anemometer type back flow arresting device on rooftop ventilating fan



United States Patent r 13,52s,297

[72] Inventor Yuzo Kawai [56] References Cited 12, Karasugatsuji-cho, Tennouji-ku, Osakwshi Japan UNITED STATES PATENTS [21] Appl. No. 802,135 108,185 10/1870 Prentis 98/74 [22] Filed Feb. 25, 1969 808,075 12/1905 Eckhart 98/74 [45] Patented Aug. 25, 1970 1,410,624 3/1922 Sylvan 98/74 Pnomy $2553 1968 Primary Examiner Meyer Perlin 43/154152 Attorneys- Polachek and Saulsbury ANEMOMETER TYPE BACKFLOW ARRESTING ABSTRACT: The invention of the present application relates DEVlCE ON RO OF'IZOP VENTILAT FAN to a ventilation fan mounted on the rooftop which is provided 1 Clam" 4 Drawmg with an anemometer to inhibit rain and wind from sweeping or [52] US Cl 98/74, blowing into the fan assembly. The anemometer is provided 98/119 with a novel mechanism which operates the shutters of ex- [51] Int. Cl F23] 17/02 haust to open or close according to the direction of wind so [50] Field of Search 98/74, 73, that the back blow of wind or rain into the fan assembly is reduced.

Patented- Aug. 25, 1970 Sheet INVENTOR, Yuzo lfa wai Pitented Aug. 25, 1970 Sheet a of 2 I INVEN'IOR Yuzo Kan/a ATTORNEYS ANEMOMETER TYPE BACK FLOW ARRESTING DEVICE ON ROOFTOP VENTILATING FAN This invention relates to a ventilation fan mounted on the rooftop and more particularly to such ventilation fan arranged such as to inhibit rain and wind from sweeping or blowing into the fan assembly by utilizing an anemometer.

Any of the conventional ventilation fan assemblies of this type comprises a ventilating fan or fans housed in a ventilating cylinder having a top cover means and is installed on the rooftop so as to suck up by the fans the indoor air and release it to the atmosphere to thereby effect ventilation. However, it is very likely, particularly in windy or stormy weather, that the wind blows into the ventilation cylinder and forces the air stream to flow backward into the interior of the building, and as yet no effective means for preventing such phenomenon has been contrived. V g Y The present invention is designed to provide a solution to this problem. The mechanical setup of the invention will be described in detail hereinafter by way of a typical embodiment thereof. I W m. v

FIG. 1 is a longitudinal sectional side elevation of the present invention;

FIG. 2 is a sectional view as taken on line A A of FIG. 1;

FIG. 3 is an enlarged sectional view of the principal parts of the present invention; and

FIG. 4 is a diagrammatic operational illustration of the present invention.

Referring generally to the drawings, numerical sign 1 designates the fans housed in a ventilation cylinder 2, and 4 a top cover member capped over the top opening of said ventilation cylinder 2 and having an air passing opening 3 around its periphery. In the center of said cover member 4 is mounted a box 6 composed of two headless conical columns 5, 5 which are arranged opposedly in a reversed relation to each other, and in the center on both top and bottom of said box 6 are provided the radial ball bearing holding members 7, 7' which hold the double row self-aligning radial ball bearings 8, 8', respectively. It will also be noted that a return spring 9 is mounted in either upper or lower part of the box and that a driven'shaft l0 and a main shaft 11 are provided uprightly so that they may rotate and may also rise and fall. In the embodiment shown, said return spring 9 is seen mounted on the driven shaft 10, but it may be mounted on the main shaft 11 to attain the same effect.

Numerical sign l2 denotes a radial ball bearing holding member which holds thereon a double row self-aligning radial ball bearing 13 and is secured to an end of the driven shaft 10 to thereby rotatably and foldably couple the main shaft 11 thereto. As will be understood, this double row self-aligning radial ball bearing 12 and its holding member 13 may be fitted to an end of the main shaft 11 to couple it to the driven shaft 10 in the same manner as described above to attain the same effect. Also in the drawings, 14 denotes an anemometer having a wind vane 15 mounted vertically adjustably toward the top of the main shaft ll, l6, 16 the equally multi-sectioned cable anchoring plates rotatably and slantably mounted at the lower end of the driven shaft 10, 17's the cables each having its one end slidably secured to the corresponding anchoring plate'l6 and its other end anchored to a shutter 19 of a size sufficient to intercept the air passing opening 3, said shutter being provided on the inside of each of the four peripheral walls 18, and 20's the bearing portions which rotatably support the shutters 19. It will also be noted that the four cables 17, corresponding to the peripheral walls, are arranged crosswise at right angles to each other at the bottom end of the main shaft 10 Return springs may be provided to the four shutters to keep them normally in an open position. In the embodiment shown, the ventilation cylinder 2 is formed square with the four faces facing -respectively east, west, south and north, but said cylinder 2 may be formed circularly and such circular cylinder may be equally multi-divided and may be provided with the correspondingly divided shutters. In each case, the resulting effect is substantially same. In the figures, 21 denotes a motor and 22 a coupling member which connects the ventilation cylinder 2 and the cover member 4.

In operation of the present invention having the above described construction, first the motor 21 is actuated to rotate the fans 1, whereby the indoor air is sucked up to rise from the top openings of the ventilation cylinder 2 and is then discharged outside through each opening 3 surrounded with the four peripheral walls 18 of the top cover member 4, in the same manner as conventionally practiced. In the present invention, however, an anemometer 14 is provided uprightly through the main shaft 11 on top of the cover member 4, and said main shaft 11 is arranged rotatable with the aid of the double row self-aligning radial ball bearing 8 and its holding member 7 and is also so arranged as to be vertically movable in the manner of a beam scale, or free to rise or fall with said double row self-aligning radial ball bearing 8 as the fulcrum. It is also to be noted that the bottom end of this main shaft 11 is coupled, through a holding member 12 of a double row selfaligning radial ball bearing 13, to the top end of the driven shaft 10 which is rotatably and vertically movable supported by the double row self-aligning radial ball bearing 8' and its holding member 7 in the same manner as said main shaft 11.

Therefore, as shown in a diagrammatic operational illustration of FIG. 4, when the wind is blowing for example from the east, the upper half of the main shaft 11 is slanted to the west side with the radial ball bearing 8 as the fulcrum in the manner shown by one-dot chain line since the vane of the anemometer 14 receives the easterly wind, while the lower half of the shaft is slanted to the east side. Since the bottom end of the main shaft 11 is joined to the drive shaft 10 through the double row self-aligning radial ball bearing 13, the driven shaft 10 has its upper half portion accordingly slanted to the east side with the double row self-aligning radial ball bearing 8 as the fulcrum in the manner shown by the one-dot chain line, while the lower half of the shaft 10 is slanted to the west side. Accordingly, the cable anchoring plate 16 rotatably and slantably coupled to the bottom end of the drive shaft 10 is shifted from the position a to position b, namely to the west side (see FIGS. 3 and 4). This shift results in stretching the cable 170, whereby the shutter 19a on the peripheral wall l8 facing the east is turned to move from its position indicated by the solid line in FIG. 1 to the position shown by the phantom line to thereby shut the opening 3, thus inhibiting the easterly wind from entering said opening down into interior of the ventilator.

When the anemometer receives the westerly wind, an action diametrically opposite to the above described case is effected in the manner shown by the two-dot chain line in FIG. 4, thus closing the shutters on the west side. On subsidence of the easterly wind, the main shaft 11 and the driven shaft 10 are returned to their original positions by the action of the return spring 9, thus again opening the corresponding shutters. This return spring may as well be provided on the main shaft 11 side to obtain the same effect.

While the above discussion was centered around a case in volving the easterly wind, it will be understood that the similar effect is attained for the westerly, southerly or northerly wind; the shutters on the respective side are closed corresponding to the rotation of the anemometer caused by such wind received on the vane 15. As will also be obvious, for an obliquely blowing wind such as an east-southerly or west-northerly wind, the shutters 19a, 190, or 1%, 19d on the east-south or west-north side, respectively, are closed accordingly.

The present invention also permits free operational adjustment of the shutters correspondingly to the blown-in wind pressure since the leverage may be varied by vertical adjustment of the anemometer mounted on the shaft 11. Further, since pressure of the spring 9 can be adjusted by vertical movement of the cylinder secured by bolt means to the driven shaft 10 at the bottom end of the radial ball bearing holdmember 7 it is possible to regulate the force of restitution of v the main shaft 11 as well as the driven shaft and to effect operational adjustment of the shutters correspondingly to the blown-in wind pressure.

As depicted in the foregoing, the present invention is provided with a plurality of shutters adapted to open or close the air passages, such shutters being coupled by the main shaft 11 and the driven shaft 10, which are arranged rotatable and able to rise and fall, and by the cables 17, and specifically said main shaft 11 and driven shaft 10 are journalled by the respective double row self-aligning radial ball bearings, so that it is possible to effect smooth automatic opening and closing, with little resistance, of one or two shutters on any side corresponding to the wind direction by utilizing the wind itself as the power source. Moreover, the construction is very simple and any undesirable back flow, which may otherwise be caused by rain and wind, is perfectly inhibited, thus permitting to maintain an optimum indoor air conditioning. Thus, the present invention offers a device of high practical value, whereby besides indication of the wind direction, highly effective ventilation of the indoor air is performed with markedly improved function of the ventilation fan.

lclaim:

1. An anemometer type back flow arresting ventilation fan device mounted for use on rooftop, in which a box composed of opposed column elements is provided in the center ofa top cover member crowned over the top periphery of a ventilation cylinder having fans housed therein while forming the air passing openings around said periphery; a main shaft and a driven shaft are provided uprightly to extend through the center of said box, said both shafts being arranged rotatable and able to rise and fall through the aid of the radial ball bearing holding members, the double row self-aligning radial ball bearings, and a return spring; a ball bearing holding member having therein a double row self-aligning radial ball bearing is coupled to an end of said driven shaft or main shaft to thereby couple said both shafts such that they are rotatable and able to rise and fall; an anemometer having a wind vane is mounted at an upper part of said main shaft; and equally multisectioned cable anchoring plates are rotatably and slantably fitted at the bottom end of said driven shaft, with one end of each of said cables being slidably secured to the corresponding one of said anchoring plates, with the other end being coupled to the corresponding one of the several equally sectioned shutters adapted to open or close said air passing openings. 

